Compared to Lightwave 7.5 and C4DXL7 I would say that Carrara 2.1 WIN98SE has been somewhat less stable (I also have a dual-boot with WIN2K and Carrara didn't seem any more stable on that OS); I can't recall the last time I had a crash in either Lightwave or C4D but Carrara crashes (or just gets weird to the point where I have to shut down and sometimes even have to revert to a previous version of a scene or sometimes even start over from scratch) with some regularity. I tend to use a lot of third-party plug-ins and sometimes I wonder if those might be the culprit although it's hard to know for sure. Carrara has gotten more robust over time and hopefully C3 will be even better in this regard than C2. I would imagine that robustness/stability are particularly important for those trying to make money using Carrara (vs. hobbyists who might be willing to put up with more weirdness in exchange for cost-effectiveness and useful features).